David Catcheside was one of the seminal figures in the post-war
development of genetics, both in the United Kingdom and Australia.
He made distinguished contributions in several different areas:
plant genetics and cytology, the genetic effects of radiation,
fungal biochemical genetics, controls of genetic recombination
and, in his retirement, bryology. As a teacher and postgraduate
supervisor he played a large part in launching the next generation
of geneticists in both hemispheres. As a professor and administrator
he was responsible for several new institutional developments
including the first Australian Department of Genetics, the first
Department of Microbiology at Birmingham and, perhaps most importantly,
the Research School of Biological Sciences of the Australian National
University.

Family Background and Education

The Catcheside family name derives from a hamlet, Catcherside,
in Northumberland, and David Catcheside's great-grandfather Thomas
Catcheside was a farmer in Jarrow and a shop-keeper in Newcastle.
Thomas's children, two daughters and two sons, became orphans
and were looked after by an aunt, Anne Guthrie. In 1850 all four
emigrated to South Austrralia, and the two sisters stayed permanently.
The older brother, the first of three in successive generations
to be named David Guthrie, farmed in South Australia for a number
of years, did some prospecting for gold, developed an enthusiasm
for painting and, in 1862, returned to England to learn photography.

Back in the home country, he married the daughter of a Bristol
umbrella manufacturer and turned to that trade himself, while
continuing with his painting. In the next generation the family
combined trade and educational interests. David's father, the
second David Guthrie (born 1879), was a wholesale draper in London,
and his uncle, his father's younger brother, was the headmaster
of a school near Waterloo Bridge. David's mother, the daughter
of a solicitor's clerk of artistic inclinations (he illuminated
manuscripts as a sideline), was a teacher before her marriage.

David grew up in Streatham, the first of two children, four years
older than his sister Phyllis. From an early age he showed a keen
interest in plants and animals, collecting butterflies, beetles,
fossils, birds' nests and eggs, and keeping small aquaria. This
interest, particularly in plants, was further fostered in the
grammar school, Strand School, Brixton Hill, to which he won a
Junior County Scholarship in 1918. Although he did not study Biology
as a school subject, he accumulated a large herbarium of flowering
plants and ferns which he later donated to King's College London.
In his first year at the Strand School he attended a weekly class
on Nature Study given by S.T.S. Dark, the Physics Master who also
organized the school Natural History Society of which David became
an enthusiastic member. In their second year, pupils were separated
into 'classical' and 'modern' streams, the latter involving more
science. Under protest, David was 'pushed' into the classical
stream and had, as he later put it, to suffer Latin for four years,
although the course did include a great deal of mathematics and
some science. When, in 1923, he entered the sixth form he switched
to science, studying Pure and Applied Mathematics, Chemistry and
Physics for his Higher School Certificate, which he took in 1925.

Through the school Natural History Society he met W.R. Sherrin,
Curator of the South London Botanical Institute, who as a guest
lecturer stimulated David's life-long interest in mosses and encouraged
him to join the British Bryological Society. Sherrin also introduced
him to a number of professional botanists, including the bryologist
H.N. Dixon and the mycologist J. Ramsbottom. It was again through
Sherrin that David met his near-contemporary P.W. Richards, a
fellow moss enthusiast who, more than a decade later, became a
colleague in the Cambridge Botany School. All of these helped
to confirm his interest in Botany as a future career.

His head master, R.K. Gutner, persuaded his parents to allow him
to seek entrance to the University of London. He applied to King's
College, and R. Ruggles Gates, Head of the Botany Department,
accepted him for admission to the Honours School of Botany on
condition that he read Intermediate Botany in his first year to
compensate for the lack of Botany in his H.S.C. Although Gates's
own specialism was in cytology and genetics, and these were the
main fields of research in his department, the collegiate undergraduate
course was typical of the time in having no genetic component.
It consisted predominantly of a detailed study of the major plant
phyla coupled with plant physiology, which was taught by E.C.
Barton-Wright. David supplemented the collegiate course by taking
Gates's University of London intercollegiate course on Cytology
and Genetics, as well as other courses on Algae (F.E. Fritsch),
Ecology (F.W.Oliver) and Plant Palaeontology (W.T. Gordon, a lecturer
whom he particularly appreciated). He was required to study subsidiary
Chemistry in his second and third years, and in his third year
he also took Biochemistry, which, for the first time, was allowed
as a subsidiary subject at King's.

During the summers of 1926, 1927 and 1928, David assisted Gates
in an investigation of the inheritance of petal length in Oenothera,
and so was introduced to the genus to which he was to devote
much of his earlier research. Perhaps even more important in shaping
his future career was his attendance in 1928, after completing
his degree examinations, at the first Summer School at the John
Innes Horticultural Institution at Merton, South London. It was
given by an array of leading geneticists including J.B.S. Haldane,
C.D. Darlington, R.C. Punnett, M.B. Crane and W.J.C. Lawrence.
There were at least two lectures a day given chiefly by Haldane
(genetics) and Darlington (cytology), coupled with a series of
laboratory demonstrations. This three-week course was a revelation
to him.

David graduated in 1928 with First Class Honours, and was awarded
the Jelf Medal for Science, having already, in 1927, won the Carter
Prize for Botany. He took the B.Sc. of London University but not
the Associateship of King's College (A.K.C.), which would have
required an additional examination in Divinity. A third of a century
later this lack of formal recognition by his alma mater was repaired
when King's College offered him an Honorary fellowship, which
he accepted.

His time as a student at King's College was well spent in another
way, for it was there that he met his future wife, Kathleen Mary
(nee Whiteman), a fellow student and Botany graduate. They were
married in 1931.

Glasgow, London and Oenothera

After gaining his B.Sc. David did not proceed to a Ph.D., since
that would have required him to live at his parents' expense,
the grants then awarded covering only fees and fares. Academic
positions were few and far between, but he was fortunate to be
offered the post of assistant to the Professor of Botany (J.M.F.
Drummond) in the University of Glasgow. Here, from October 1928,
he taught cytology to advanced students, demonstrated in practical
classes to the first year and to medical students, and started
research, entirely by himself, on Oenothera cytology.

It was already well known through the work of several cytologists,
including Ruggles Gates, that one group of Oenothera species
with 2n = 14 assembled all 14 chromosomes into a continuous ring
at the first metaphase of meiosis, with alternating orientation
of centromeres ensuring a 7-7 disjunction at anaphase-l. It was
also known, following the work of Otto Renner, that these species
were permanently heterozygous, regularly segregating distinct
7-chromosome complexes, with each complex inviable when homozygous.
The explanation for the formation of the ring of 14 was still
controversial at that time, though R.E. Cleland in America had
suggested the correct explanation. Cleland proposed that the two
complexes in each species had diverged through a series of interchanges
of distal segments of chromosome arms, so that if one complex
had the arm arrangement A-B C-D... K-L M-N the other would be
B-C D-E ... L-M N-A. The ring of 14 could then be accounted for
by conventional homologous pairing of chromosome arms followed
by chiasma formation and terminalisation in each arm.

Darlington set out the argument in detail in a paper in 1930.
Others, however, including Ruggles Gates, preferred to account
for rings of 14 by the alternative hypothesis of telosynapsis,
invoking a general mutual attraction between chromosome ends.

David's first paper, published in 1930 in the Transactions
of the Royal Society of Edinburgh described patterns of chromosome
catenation and disjunction in two ring-forming diploid species
of Oenothera and also in a triploid strain that he had
discovered in one of them (Oe. pycnocarpa), It was a bold
paper for a 23-year-old, offering not just description but also
decisive evidence, as he believed, for telosynapsis. His critical
observation was the apparent formation of circles of 21 chromosomes
in the triploid, which was not compatible with specific pairing
of rearranged chromosome arms, given just two different complexes
with one in duplicate. As can be seen from the careful drawings
with which he illustrated his paper, the distinction between genuine
joining and mere proximity of small chromosomes, arranged in sectioned
material at different focal levels, must have been far from easy.
The reality of the ring of 21 was promptly disputed by Darlington
who, having examined Catcheside's slides, published a challenging
note in Nature. The disagreement was not prolonged. After
more observation and further thought, David accepted Darlington's
view, attributing his own error to difficulties of interpretation,
'together, perhaps, with prejudiced preconception'. It is a reasonable
presumption, though he did not say so, that the prejudice arose
from too much respect for the views of his former Professor. He
later commented, in a somewhat less than eulogistic obituary,
that Gates himself eventually 'came to accept the views of Renner,
Darlington and Cleland though grudgingly and preserving some of
his own earlier errors'.

In 1931, David returned to King's College's Botany Department
to take up an Assistant Lectureship. Here he assumed wide-ranging
teaching duties, lecturing not only in genetics and cytology but
also on algae and plant physiology. In 1933 he was promoted to
the grade of Lecturer. Throughout his five years on the staff
at King's he continued work on Oenothera, initially with
Ruggles Gates but later by himself. He profited from contacts
with the John Innes Horticultural Institution, where L.F. La Cour
was developing new cytological techniques and K. Mather was available
for help with stati»ties. Most of this research was concerned
with the working out of the structural relationships between the
chromosome complexes of various Oenothera species and varieties,
and was essentially a consolidation of Cleland and Darlington's
general model. But from 1935 he started to break newer ground
with experiments on the genetic effects of X-rays, and obtained
both new segmental rearrangements and some gene mutations.

This phase of his career culminated in 1936 with the award of
the University of London D.Sc., based on his published papers
on Oenothera. The respect that he already enjoyed in the
U.K. genetics community is shown by his appointment in 1935 as
Secretary of the Genetical Society, a position that he held until
1941.

The California Interlude

In 1936 David Catcheside was awarded a Rockefeller International
Fellowship to work in the Biology Division (the Kerkhoff Laboratory)
of the California Institute of Technology in Pasadena. Here he
came into contact with a now legendary group of geneticists, mainly
concerned with the fruit fly Drosophila, including T.H.
Morgan, A.H. Sturtevant, C.B. Bridges, Th. Dobzhansky, Jack Schultz
and Sterling Emerson (who worked on both Drosophila and
Oenothera), as well as with the maize cytologist E.G. Anderson.
He also enjoyed a visit of one month to the Connecticut Agricultural
Experiment Station, where he came to know two leading maize geneticists,
L.J. Stadler and D.F. Jones.

During his American year, David continued with some work on Oenothera,
but devoted most of his time to radiation studies on the two
premier genetic organisms of the day, Drosophila melanogaster
and Zea mays. Whereas he had first become interested
in X-rays as a source of new genetic markers for mapping Oenothera
chromosomes, he was now more concerned witth the mode affaction
of the radiation. In particular, he wanted to distinguish between
two possible mechanisms of formation of segmental interchanges:
random breaks followed by more or less indiscriminate fusions
of broken ends, and initial inter-chromosome contact followed
by breaking-rejoining at the contact points. The two hypotheses
predicted differently shaped curves relating radiation dose to
yields of rearrangements. In Drosophila, using the giant
polytene chromosomes, he found a dose-effect relationship approximating
to linearity over the range of doses used and this did not enable
him to make a decision between the hypotheses under test. In addition,
he carried out a more limited survey of the types of rearrangements
induced in maize and observed at pachytene of meiosis, and drew
the conclusion that the more complex rearrangements could be most
easily explained on the breakage-first hypothesis.

The Cambridge Years

While at CalTech David was invited to a Lectureship in Cambridge
by Professor F.T. Brooks, the head of the Botany School. David
took up the position on his return to Britain in 1937 and was
to remain in Cambridge for 14 years. Paul Richards, who was already
in the Botany School, sums up the effect that David had on the
department in the words 'He brought us into the modern world'.

As a London graduate, David was something of an outsider in Cambridge.
London was beyond a pale that enclosed only Cambridge, Oxford
and Trinity College Dublin, and so his higher doctorate was not
recognized; he was officially referred to as Mr Catcheside. He
was never totally convinced of the benefits of the Cambridge system,
thinking the colleges something of a distraction from University
teaching and research. Nevertheless, he achieved considerable
recognition from both sides of the system over the years. In 1944
he was elected to a fellowship in that most splendid College,
Trinity, and in 1950 he was promoted to a Readership in Cytogenetics
in the Botany School. On a less academic level, he was entrusted
with the job of Air Raid Warden during the war years, with special
responsibility for the Downing Street science site.

Genetics had been first represented in Cambridge by W. Bateson,
the leading protagonist of Mendelism in Britain from 1900 onwards,
who moved to become the first Director of the John Inner Horticultural
Institution in 1910. In 1912, R.C. Punnett became the first occupant
of the Arthur Balfour Chair of Genetics in the University, and
he was still in post at the time of David's arrival. When he retired,
David Catcheside applied for the chair but cannot have been surprised
when the University's choice fell on a far more senior candidate,
R.A. Fisher, the eminent statistician and population geneticist.
Fisher took up the appointment in 1943 and established a small
Department of Genetics based, as in Punnett's day, on Whittinghame
Lodge. Recognizing the lack of undergraduate teaching in genetics
in the University as a whole, he joined with David in proposing
an undergraduate course in genetics for Part II of the Natural
Sciences Tripos, but they obtained no support. Fisher did succeed
in starting a Genetics Part II course in 1953, after David had
left Cambridge.

David's own teaching continued to be confined to students taking
the Botany Tripos. This was almost the only instruction in general
cytology and genetics then available in Cambridge. The Zoology
Tripos included no genetics whatsoever, and although R.A. Fisher
gave an annual series of lectures outside the Tripos, they tended
to be too mathematical for most biology students. From the start,
David taught genetics and cytology in Part II Botany and, a little
later, took over an extensive Part I course in which he provided
an introduction to genetics and a geneticist's view of botany,
with emphasis on evolution. He also took part in field trips,
helping particularly with identification of mosses. He was never
a charismatic lecturer but he was, nevertheless, an effective
teacher. Those who took his Part I and Part II lectures, including
one of us (JRSF), can testify to their precision, clarity and
forward-looking perspective. In 1945-46 he introduced the Part
II class to the beginnings of biochemical genetics and, although
Watson and Crick were not yet heard of, he gave good reasons for
expecting great things from DNA. His ability in laboratory classes
to select an anther from a bud and make from it a perfect microscopic
demonstration of any desired stage of meiosis, all within two
minutes, excited both admiration and envy.

David's influence was even stronger at the postgraduate level.
He had a generally relaxed style of supervision of postgraduates;
though he was ready with suggestions when necessary, he liked
his students to follow their own interests. He once said to one
of us (JRSF): 'Thinking of the project is the most important port
of a Ph.D. Why should a supervisor have to do that for a student?'
Such an attitude would hardly be regarded as proper today, and
he certainly modified it in later years, but in his Cambridge
group it worked. In the years immediately after the war he provided
unobtrusive but attentive guidance to students engaged on a great
range of projects, nearly all, as it turned out, leading to Ph.Ds.
In more or less chronological order, they included J.L. Crosby
(homostyly in primrose populations), H.L.K. Whitehouse (genetics
of the fungus Neurospora sitophila), J.M. Thoday (radiation
effects on chromosomes), E.J. Godley (from New Zealand, chromosomes
of grasses), J.R.S. Fincham (genetics and cytology of Neurospora
spp.), M. Ahmed (Pakistan, mating-type mutation in yeast),
Jean M. Mathieson (Australia, genetics of various Ascomycete fungi),
Margaret Blackwood (Australia, tetraploid maize), G.W.P. Dawson
(genetics of bacteriophage), C.J. Shepherd (enzymes in Neurospora),
J.N. Hartshorne (Chlamydomonas genetics), J. Venkateswarlu
(India, maize cytology), G.W. Grigg (Australia, mutagenesis in
micro-organisms). Most of these students went on to teach genetics,
or even eventually to occupy chairs, in other universities. David
sent us on our way equipped with Drosophila and maize stocks,
and instructions on how to use them for teaching.

David's own scientific work developed in various directions during
the Cambridge years. He contributed the chapter on plant methods
to the 1937 edition of Bolles Lee's Vade Mecum, a standard
cytologists' reference book, and maintained it through several
further editions. He continued his studies on Oenothera, mainly
with the structurally homozygous diploid Oe. blandina in
which he discovered a clear and beautiful example of position-effect
variegation resulting from one of his radiation-induced segmental
interchanges. Two genes, governing sepal and petal pigmentation
respectively, were inactivated in some but not all cell clones
when the chromosome region containing them was brought close to
heterochromatin. The affected genes regained full activity when
restored to their normal chromosome environment by meiotic crossing-over.
This kind of position effect was already well known in Drosophila,
but Catcheside's example was, and still is, the only one known
in plants. Today it could be investigated at the molecular level,
but unfortunately the interchange stock was lost following David's
second move to Australia.

His most substantial body of research in Cambridge was an extension
of his interest, fostered at CalTech, in genetic and cytological
effects of radiation. He established a fruitful collaboration
with D.E. Lea, a biophysicist working in the Strangeways Laboratory.
Catcheside did the genetics and cytology and Lea provided the
radiation expertise and physical theory, though David himself
became quite conversant with the physics. Between 1942 and 1946
they produced a series of papers providing quantitative data on
dose-effect relationships with different kinds of ionizing radiation
- X-rays, -rays and neutrons, They used Drosophila for
detecting chromosomal rearrangements and gene mutations and (with
J.M. Thoday) pollen grain mitosis in Tradescantia bracteata
for rearrangements and chromosome breaks. In brief, they found
that yields of chromosome breaks and dominant mutations were proportional
to radiation dose, and were thus presumably one-hit events, whereas
segmental interchanges occurred in proportion to something less
than dose-squared, consistent with predominantly two-hit events.
Comparisons of the efficiencies of different kinds of radiation
in inducing chromosome breaks led to the conclusion that, at equal
dosages in terms of roentgen units (measuring total ionizations),
the efficiency increased with the density of the ionization tracks.
'One hit' was therefore not a single ionization but rather a cluster
of ionizations all falling within the target area.

Comparison of the effects of soft X-rays of different wavelengths
made it possible to calculate that some 15 to 20 ionizations were
needed to break a Tradescantia chromatid. The Tradescantia
experiments also yielded some information on chromosome structure
and replication. There was no significant departure from random
joining of broken chromosome ends such as might arise from proximal-distal
structural polarity within chromosome arms. Chromosomes changed
from being single to double targets (separately breakable chromatids)
about mid-way through mitotic interphase.

Much of this work is summarized in Lea's book Actions of Radiations
on Living Cells (Cambridge University Press, 1945) and in
a long review article by Catcheside in the 1948 volume of Advances
in Genetics. The collaboration was terminated by Lea's untimely
death in 1947 but David, now a leading authority in a field made
alarmingly topical by the threat of atomic warfare, continued
to write reviews and give seminars on radiation effects for a
number of years.

lt was in Cambridge that he first became interested in fungal
genetics, and especially in Neurospora, which later became
his main experimental organism. Neurospora genetics in
Cambridge was started by his research student Harold Whitehouse,
who took advantage of the presence in the Botany School of some
cultures of N. Sitophila derived from a rare English isolate.
Whitehouse was the first in the U.K. to turn to Neurospora
following the pioneering work on the genus by B.O. Dodge and C.C.
Lindegren in the U.S.A. It was his own initiative, but it fitted
well with David's own developing interest in the eight-spored
ascomycetes and the opportunities offered by their ordered meiotic
tetrads for the investigation of meiosis, particularly the possibility
of polarized segregation of alleles. Soon afterwards (1946) Beadle
and Tatum published their momentous first report of auxotrophic
mutants in N. crassa, and David Catcheside obtained cultures
of wild type end mutant strains of this species also. In 1946-47,
another of his students (JRSF) started work on comparative cytology
and linkage maps of N. crassa and N. sitophila, and
later (1498-49) on biochemical genetics of the former species.
David himself became increasingly interested in the use of micro-organisms
for biochemical genetics and began some preliminary experiments
with Neurospora. This interest found expression in a series
of lectures that he gave, starting in 1948, to a mainly graduate
audience of biochemists and others. These lectures formed the
basis of his first book, the slim but influential Genetics
of Microorganisms, published in 1951.

David's research in the Botany School was supported on the modest
scale characteristic of those times. When he first arrived in
the Botany School there was no adequate microscope for him and
there was an interval of a year during which he had to borrow
from King's College the microscope that some years earlier he
had managed to obtain from the Dixon Fund of the University of
London. In order to grow his Drosophila cultures, he had
an incubator built from wood and plaster-board, heated by a filament
lamp controlled by a relay. With the end of the war, apparatus
became more freely available, and David obtained more space for
his growing group of research students and the services of a versatile
full-time technician, 'Nobby' Clark. For several years, also,
his wife Kathleen provided him with part-time research assistance.
It was by no means a bad situation by the standards of the times,
but there is no doubt that he was ambitious for something better.

In 1947 a new possibility opened up with the impending retirement
of Professor Brooks. In the opinion of many, David Catcheside,
with his combination of modernity and broad knowledge of traditional
botany, was an obvious candidate for the Botany chair, and there
is no doubt that he was interested. From his genetical vantage
point he took a more inter-disciplinary view of biology than was
common at the time, and he certainly had ideas both on the organization
of the Botany curriculum and on the place of genetics teaching
in the University generally. There was, however, another strong
candidate for the chair in the person of the distinguished pollen
analyst and ecologist Harry Godwin. The Appointments Committee
was split between supporters of Catcheside and Godwin and finally
resolved their dilemma by inviting one of their own number, the
senior plant physiologist G.H. Briggs, to take the post; Godwin
was his eventual successor.

David's disappointment must have made him more ready to consider
a move from Cambridge. His promotion in 1950 to the rank of Reader
was no doubt some compensation, but it did not bring with it the
increased resources for genetics that he would have liked, He
had, in fact, already considered a move a few years previously
when, following a spell of indifferent health, his doctor had
recommended a change to a better climate. He carried this suggestion
into effect for several months in 1947, which he spent in California
at Stanford University studying the chromosomes of Parthenium.
argentatum (guayule), a plant that was then being promoted
as a possible source of rubber. This was probably the closest
he ever came to involvement in a project with possible commercial
implications. It is clear from his correspondence with G.W. Beadle
that he had the offer of a long-term position at Stanford, but
in the end decided against it. He later recalled that although
California had been good for his health, he had disliked the growing
climate of political intolerance, later associated with Senator
McCarthy.

In 1951 two opportunities arose in Australia. First, he was asked
whether he would be interested in the post of Chief of the Division
of Plant Industry in the CSIRO. To this inquiry he replied in
the negative, since he did not see himself as an applied scientist.
Then Ian Clunies Ross, Chairman of CSIRO and an enthusiast for
the establishment in Australia of centres for genetical training
and research, suggested that David apply for a Chair of Genetics
which the University of Adelaide was to establish in the Waite
Agricultural Research Institute. David replied positively, and
when the offer came he accepted it. Although Australia had a strong
tradition in plant and animal breeding, there was at that time
no genetics department in any of its universities. Indeed, apart
from the efforts of a few isolated individuals, notably W.E. Agar
at Melbourne, H.N.Barber in Tasmania and S. Smith-White at Sydney,
little fundamental genetics was taught at all. The new Chair of
Genetics was thus the first in Australia, and the prospect of
creating something new must have been a great attraction to David.
The Catch-eside family connection with South Australia may also
have played some part in his decision.

David took up the Adelaide appointment in 1952, the year following
his election to the Fellowship of the Royal Society of London.

Genetics in Adelaide

The new Adelaide Department of Genetics began with three members
of academic staff in addition to the Professor. Two, G.M.E. (George)
Mayo, who worked on flax and was encouraged by David to take up
quantitative inheritance, and A.T. Pugsley, a wheat breeder, were
already at the Waite Institute. For the third position, David
recruited his former Cambridge research student Jean Mathieson
(later Jean Mayo), who had returned to Australia to take up a
lectureship at the University of Melbourne.

It soon became clear that the Waite Institute was not the best
place for a general department of genetics. The then Director
(J.A. Prescott) had, it seemed, really wanted someone whose concern
was with plant breeding rather than with general and fundamental
genetics. David was disappointed with the accommodation that he
was offered and he pressed for more space for his staff, and particularly
for a teaching laboratory for undergraduates but without success.
The Waite was more an applied research institute than a teaching
establishment, and although it was formally attached to the University
of Adelaide it was a long way from the main campus at North Terrace.
Hence, in order to meet the demand from the Zoology and Botany
departments for courses in basic genetics, David and his staff
had to travel to North Terrace, transporting all the necessary
material for practical classes. In frustration, David took up
the matter with Clunies Ross, and sought his support for a move
of the Genetics Department to the main campus. He emphasised that
Genetics required the proximity of other science departments and
in particular Biochemistry, which was not represented at the Waite.
Eventually, in spite of protests from Prescott and reservations
expressed by the Vice-Chancellor, A.P. Rowe, the matter was resolved
to David's satisfaction. He was offered space in the Physics building
on the attain campus by the professor of physics, L. Huxley. An
area was converted to provide laboratories for research students
and undergraduate teaching, and staff rooms for all except Pugsley,
who remained at the Waite. This success was achieved at some cost
in terms of personal relationships, as is clear from a letter
from David to one of us (JRSF) dated December 1953:

We have been working pretty hard, not least
to get some proper courses organized and a place in which to do
them and our research under one roof. It has been a hard fight,
but we've won, I hope, and can look forward to the development
of genetics here more smoothly. The major trouble arose from crass
ignorance of what genetics was and some frankly wanted merely
plant breeding and tried to cash in on the development. The result
is no doubt a lot of local enmity, but the ultimate result seems
assured and the next incumbent won't have to fight the same battle.

David's struggle with the Adelaide establishment was something
of a cause celebre, but its successful outcome represented
a turning point for genetics in Adelaide and arguably for the
teaching of the subject in Australia as a whole. It enabled the
department to introduce a third-year advanced course in genetics
in addition to the already established half-subject courses for
first- and second-year undergraduates in Botany and Zoology. The
department was thus able to recruit science students as well as
agricultural students for an honours degree. Equally importantly,
it provided expanded opportunities for Australians to obtain postgraduate
education in genetics without having to go overseas.

David Catcheside was to remain in Adelaide for less than four
years but during this brief stay he established a centre of fundamental
genetics that soon gained a high reputation for both teaching
and research. During his own time there, four graduate students,
all of whom were later to make notable contributions, were trained
in his department: J. Langridge (from New Zealand, the pioneer
of genetics of Arabidopsis), D.L. Hayman (incompatibility
in the grass Phalaris); P.G. Martin (Neurospora genetics)
and R. Oram (tetraploid maize). Through his undergraduate teaching
he also influenced the future careers of P.A. Parsons (Drosophila
population genetics) and K. Shepherd (wheat breeding).

David barely had time in Adelaide to establish any new lines of
research of his own, but he did take further steps towards adopting
Neurospora as his main experimental organism. The first
task was to extend the range of available mutants, and he successfully
adapted for Neurospora a filtration-enrichment method for
the mass isolation of nutritionally exacting mutants which Nils
Fries, in Norway, had originally devised for the fungus Ophiostoma
multiannulatum. In collaboration with Jean Mathieson he obtained
and started characterising an extensive series of histidine-requiring
mutants, and showed that other amino acids could compete with
histidine for uptake from the growth medium. He also continued
with some work on plant genetics, publishing on the formal genetics
of maize tetraploids and on Oenothera, assigning De Vries's
classical mutant brevistylis to a particular chromosome
of the Oe. Lamarckiana complex.

Birmingham and Neurospora Genetics

In 1955 David was invited to a new chair of Microbiology at the
University of Birmingham, a post that he was to hold for the next
eight years. He later wrote (letter to JRSF, October 1993):

There werc several attempts to 'rescue' me from
the 'colonies'. Maskell, formerly of Cambridge, then Professor
of Botany at Birmingham, made one. The Birmingham option intrigued
me because it was intended to try to fuse microbial genetics with
Chemistry and Biochemistry.

He must also have been attracted by the prospect of renewing contact
with Kenneth Mather, who now headed the Genetics Department of
the University and doubtless played a leading part in the issuing
of the invitation. Mather's department was a stronghold of cytology
and biometrical genetics, especially of plants and Drosophila,
but had at that time relatively little interest in the biochemical
arid molecular side of the subject. With the new importance of
microbial genetics and DNA, there was an obvious gap to be filled,
and the new Microbiology Department was seen as a means of filling
it. David took up his new post in 1956.

His main intention was to establish a group that would contribute
to the new field of molecular biology, which he saw correctly
as the key to the future of biological science. The two strands
of molecular biology at that time were microbial genetics and
macromolecular biochemistry, and he recruited to his new department
with a view to bridging between these hitherto somewhat distant
fields. As microbiologists he obtained R.B. Drysdale, J.H. Hopton
and, somewhat later, the bacterial geneticist D.A. Smith, and
as biochemists E.H. Creaser (proteins) and A.R. Peacocke (nucleic
acids).

The DNA work was discontinued after a few years when Peacocke
left for Oxford, but not before Peacocke's research student Kenneth
Murray, who was later to become a pioneer of DNA technology, had
obtained his Ph.D. The rest of the department developed a coherent
research programme centred around gene structure and gene-protein
relationships.

The undergraduate teaching was broadly-based, including microbial
classification and physiology, but the strongest emphasis was
on biochemistry, molecular biology and genetics. The Microbiology
final-year Honours class had in most years only some four to six
students who, in the course of their individual research projects,
became integrated into the department more like research students
than undergraduates. David's Birmingham school launched some notable
scientific careers - A.C. Minson, now Professor of Virology in
the Cambridge University Pathology Department, and R.B. Flavell,
the present Director of the John Innes Centre in Norwich, were
both his graduates.

The Neurospora work was carried on by David and several
able research students, especially Noreen Murray (now F.R.S. and
a Professor in Edinburgh), Adrienne Jessop and Brian Smith (afterwards
lecturers in Genetics in Glasgow and Aberdeen respectively), and
his own son David E.A. Catcheside, now at Flinders University,
Adelaide. Their work was based to a large extent on the extensive
collection of nutritionally-exacting (auxotrophic) mutants obtained
through Catcheside's filtration-enrichment method. The emphasis
was on assigning mutations to genes by complementation tests,
uncovering functional complexities within genes by demonstrations
of allelic complementation represented by complementation maps,
and ordering the mutational sites within genes by recombinational
mapping.

David Catcheside did not discover allelic complementation, but
he was one of the first to look for it systematically over a range
of different genes. His conclusion, quite surprising at the time,
was that most genes, even if by biochemical criteria their mutation
affected single enzymes, would show complementation between certain
pairs of mutant alleles if enough mutants were looked at. He was
also probably the first to suggest the general explanation for
this initially disturbing phenomenon. In his paper (with Anne
Overton) for the 1959 Cold Spring Harbor Symposium he proposed
that it was due to interactions between different mutant forms
of the same polypeptide within an oligomeric enzyme protein. One
of us (JRSF) remembers him saying that 'a polypeptide chain is
not an enzyme', a perceptive remark at a time when the importance
of the steps leading from primary translation product to mature
protein was not widely appreciated.

It was, however, the recombinational mapping of mutant sites within
genes that provided the dominant research interest for the later
part of his career. The first breakthrough came at the end of
his time in Birmingham through the work of Adrienne Jessop on
fine-structure mapping of the his-1 gene. The frequency
of recombination between his-1 mutant sites was found to
vary over a ten-fold range depending upon the allele present at
an unlinked locus named rec-1; low recombination (rec-1+)
was dominant to high (rec-1). The variation at rec-1
occurred between the various wild-type strains that had contributed
to the experimental breeding stocks. These results were published
by Jessop and Catcheside in 1965, after his move back to Australia.

During the Birmingham years, David resumed his leading role in
the affairs of the U.K. Genetical Society, of which he had already
been Secretary and Treasurer. He served as President from 1961
to 1964.

Canberra, the R.S.B.S., and Controls of Recombination

David had been elected as a foundation Fellow of the Australian
Academy of Science in 1954 while still at Adelaide, and throughout
his Birmingham period he retained close ties with Australia. He
had participated in discussions on a proposal to establish a Research
School of Biological Sciences (RSBS) within the Institute of Advanced
Studies (IAS) at the Australian National University in Canberra.
This prestigious Institute occupies a unique position in Australia
as a centre for research and postgraduate training without involvement
in undergraduate teaching, which it leaves to the School of General
Studies of the University. In 1968 David was invited to become
a candidate for the Chair of Genetics in the John Curtin School
of Medical Research in the IAS, and he was appointed to that position
in 1964. He admitted later that his appointment was something
of an anomaly, since what the John Curtin School really needed
was a group working on human genetics. Perhaps it was seen as
a means of involving him in the detailed planning for the establishment
of the RSBS. Soon after his arrival he was appointed 'Adviser
to the University on the Development of Biological Research in
ANU'. This left him little time for personal research, but he
had some good technicians and a research assistant and so was
able to continue investigations into recombination control in
Neurospora. Two former Birmingham research students, B.R.
Smith and D.E.A. Catcheside, who had come with him to Canberra,
took on certain aspects of the work. David himself, living only
a short distance from the laboratory, found it convenient to come
in on Saturdays and Sundays to record results and set up new experiments.

When the RSBS was finally established in 1967, David Catcheside
became its first Director. There is little doubt that his intention
was to emulate the situation that he encountered at CalTech some
30 years earlier, where the Division of Biology was unified without
any formal departmental structure. In that way, he believed, fruitful
interactions between different specialisms, particularly between
Genetics and everything else, could be maximized. He had already
successfully argued the case for the integration of biology in
a different Australian context. In 1961, following a three-month
visiting professorship at CalTech, he and Kathleen had travelled
on to Australia primarily to see their daughter Patricia and her
children in Adelaide. There, he had become involved in discussions
about the development of biology at a new campus of the University
of Adelaide at Bedford Park, which afterwards became Flinders
University. David's case for an integrated School of Biology was
put into effect when the new university was eventually established.

David's integrationist viewpoint did not, however, prevail so
easily at the new RSBS. In the event it proved impossible to recruit
the desired leading researchers without allowing them some departmental
identity. By becoming a school of departments the RSBS also became
a school of compartments, partly because the component disciplines
were initially dispersed between different buildings. Apart from
Genetics itself, which was transferred from the John Curtin School
more or less intact, four additional departments were established
during David's directorship, each with a professorial head: Environmental
and Population Biology, later changed to Environmental Biology
(1967, R.0. Slatyer), Developmental and Cell Biology (1967, D.J.
Carr), behavioural Biology, later changed to Neurobiology (1969,
G.A. Horridge) and Population Biology (1972, B. John). Two of
the initial appointees later served as Directors of the School
(John 1979-1984 and Slatyer 1984-1989). To staff his own department,
David brought in C.H. Doy and two from his former Birmingham group,
E.H. Creaser and David Catcheside junior. This departmental organization
of the RSBS persisted through David's period as Director, but
has recently been replaced by a group structure more in keeping
with his original concept.

For much of his time as Director, David was preoccupied with the
administration of the new Research School and the promotion of
plans for a new building which did not fully materialize until
1973, the year following his retirement. He was also much involved
in university administration. He served as Deputy Chairman of
the Board of the Institute of Advanced Studies and presided at
the regular monthly meeting of that body. He represented the Institute
on the equivalent Board of the School of General Studies, on which
all of the teaching departments of the University were represented,
as well as on the University Council and Finance Committee. Not
surprisingly, he found it, increasingly difficult to give enough
attention to the Genetics Department itself. To remedy this situation,
he persuaded his former Adelaide research student John Lairidge,
now at the Division of Plant Industry in the nearby CSIRO, to
accept a shared post between CSIRO and RSBS and to act as Head
of Genetics.

Despite his heavy administrative commitment, he still managed,
with the help of his junior colleagues, to continue work on control
of recombination frequency in Neurospora crassa. The remarkable
finding was the multiplicity of specific recombination controls
that showed variation in the various laboratory wild-type strains.
Three controlling gene loci were identified, rec-1, rec-2
and rec-3, discovered repectively by Adrienne Jessop, Brian
Smith, and Catcheside himself. Variation in each of these had
transacting effects targeted on specific genes or specific inter-gene
intervals, resulting in up to ten-fold differences in recombination
frequency within or between genes as the case might be. Thus rec-1
acted on the genes his-1 and nit-2, rec-2
on his-3 and certain scattered short inter-gene intervals,
and rec-3 on am and his-2 and certain other
intervals.

The analysis of the rec-2-his-3 relationship, carried out
by David with his student Theresa Angel, was particularly significant,
since it identified a site closely linked to his-3, called
cog, that was involved both in the control of recombination
frequency within his-3 and in the transmission of the effect
of the dominant recombination-repressing allele rec-2+.
When the connection between cog and his-3 was disrupted
by a segmental rearrangement with a breakpoint within his-3,
only those his-3 sites that remained joined to cog
had their recombination repressed. Analysis of this very promising
system has subsequently been pursued to the DNA sequence level
by David's son, D.E.A. Catcheside.

David's knowledge of recombination research was comprehensive,
encompassing cytology as well as molecular biology, and prokaryotic
as well as eukaryotic systems. Encouraged by one of us (BJ), he
brought it all together in his second book, The Genetics of
Recombination, published in 1977. It was an admirably clear,
concise and up-to-date account of the subject as it was understood
at that time. It was probably largely in recognition of his innovative
work on recombination that he was, in the same year, elected as
a Foreign Associate of the U.S. National Academy of Sciences.

Adelaide and the South Australian Moss Flora

After his retirement from the Directorship in 1972, David retained
his connection with the RSBS Genetics Department for another three
years as a Visiting Fellow. In 1976, however, he and Kathleen
moved to Adelaide, where their daughter Patricia and son David
were now both living. There he became an Honorary Research Associate
at the Waite Institute, hut he did not continue with personal
research in experimental genetics. Instead, he used his retirement
to devote time to his long-standing and actively maintained interest
in mosses. This was more than a casual hobby. The seriousness
of his commitment was demonstrated by the publication in 1980
of his third book, Mosses of South. Australia, a comprehensive
account illustrated throughout by his own clear line drawings
of the diagnostic characters. The book was based upon his own
field work and microscopic observation, combined with library
research to clear up confusions regarding species names. It was
warmly received in the bryological community.

David continued to publish occasional papers on the moss flora
until 1993, partly in collaboration with the bryologist Ilma G.
Stone. One of his last papers (with Stone) described two new species.
He made many donations to the Adelaide Herbarium, and eventually
bequeathed to it his entire bryophyte collection together with
his microscopic slides and library.

He remained active and in good health almost to the end of his
life, but in 1990 was diagnosed as having melanoma. The primary
tumour on his ear was excised ('a sort of Van Gogh job' was his
humorously exaggerated description) and all seemed well until
the autumn of 1993 when, following some spells of dizziness, he
was found to have secondaries in the lungs and the frontal lobe
of his brain. In early December he seemed very much his normal
self, with symptoms under control and some hope of being allowed
to drive his car again. But in the following months his condition
deteriorated, and he died on the day following his 87th birthday.
He retained to the end his interest in science, and particularly
in the further progress of the recombination research.

Epilogue

David Catcheside was first and foremost a geneticist. He did not,
however, see genetics as a separate compartment of knowledge but
rather as a central element in the indivisible structure of biology,
which itself needed a sound foundation in the physical sciences.
The implications of this integrationist view for university teaching
were set out in a letter that he had published in Nature in
1963. Today, few would disagree with him in principle, though
many would doubt whether our present undergraduates could cope
with the wide-ranging curriculum that he prescribed. Certainly
he himself lived up to his own ideal, combining breadth of knowledge
and vision with meticulous attention to detail.

David's professional career was intimately linked with the post-war
rise of Genetics in Britain and Australia. Planning and administration
took a great deal of his time, but he still managed to maintain
his research. Of the total of 38 graduate students whom he supervised
over an academic career spanning 53 years, twenty became university
teachers and ten became professors. Of his Cambridge students,
three became Professors of Botany or Plant Breeding - J.G. Hawkes
(Birmingham), J. Venkateswarlu (Andhra, India) and H.S. Hsi (Jiansu,
China), and four others became Professors of Genetics - J.M. Thoday
(Sheffield and Cambridge), G.W.P. Dawson (Dublin), J.R.S. Fincham
(Leeds, Edinburgh and Cambridge) and M. Ahmad (Islamabad). From
Adelaide, Birmingham and Canberra respectively, P.G. Martin became
a Professor of Botany (Adelaide), Noreen F. Murray a Professor
of Molecular Biology (Edinburgh) and H.C. Choke a Professor of
Genetics (Kuala Lumpur). In addition, five of David's graduate
students rose to Readerships: from Cambridge, J.L. Crosby, H.L.K.
Whitehouse and M. Blackwood in Departments of Botany (in Durham,
Cambridge and Melbourne, respectively); from Adelaide, D.L. Hayman
in the Adelaide Genetics Department; from Canberra, D.R. Smyth
in the Genetics Department of Monash University. Of David's research
students who did not make their careers in universities, G.W.
Grigg, C.J. Shepherd, J. Langridge and R. Oram rose to senior
positions in the Australian CSIRO, and E.J. Godley became Director
of the Botany Division of the New Zealand DSIR.

David was an active member of thirteen learned societies. He served
as a council member both of the Royal Society (1959-61) and of
the Australian Academy of Science (1955 and 1966-69, Vice-President
in the latter years). He was over a long period a pillar of the
U.K. Genetical Society (Secretary 1935-41, Treasurer 1945-52,
President 1961-64); he later became President of the Australian
Genetical Society. From as early as 1923 he was a member of the
British Bryological Society, was an elected member of its executive
in 1958-59, and an Honorary Member from 1981. From 1981 he was
a Fellow of the Linnean Society. Less expectedly he served, in
1958, as President of the British Lichen Society. His standing
as a botanist as well as a geneticist was confirmed by his appointment
as President of the Botany Section of ANZAAS in 1973. It was characteristic
of him that when asked to perform a service he almost never declined.

In personality David was somewhat reserved and self-contained,
with a quiet strength of character. Some thought him rather cold.
But to many colleagues and students he was a true friend. For
such a busy man he was a remarkably good correspondent, nearly
always writing in his own very legible hand, rather than through
a secretary and typewriter. He was totally without ostentation
and spoke to everyone, colleagues and students alike, in the same
quiet, straightforward and often humorous manner. A supremely
well-organized person, he always had time for other people. He
will be remembered with affection and respect by many biologists
in several continents.

acknowledgments

We are especially indebted to D.E.A. Catcheside for making available
to us his father's autobiographical notes. We also thank H.L.K.
Whitehouse, P.W. Richards, J.M. Thoday, D.L. Hayman, N.W. Simmonds,
R.B. Flavell and Noreen E. Murray for useful information and comment.
The photograph of David Catcheside was taken in the RSBS, Canberra,
in 1972 by the School's photographer, Barry Parr.

This memoir was originally published in Historical Records
of Australian Scince, vol. 10, no. 4, December 1995,
pp. 393-407, and also in Biographical Memoirs of Fellows
of the Royal Society of London, 1995.